Thomas a



(No Model.)

T. EDISON. DYNAMO 0E MAGNETO ELECTRIC MACHINE.

No. 287,523. I Patented Oct. 30, 1883.

wmsssns: y

v (i 3* k I W ED I v /5L4 O ATTORNEY.

UNITED STATES 'ATENT Orrrcn.

TIIOlilAS A. EDISOIQ, OF MENLO PARK, YEW JERSEY, ASSIGNOR TO THE EDISON ELECTRIC LIGHT COMPANY, OF NE T YORK, N.

DYNAMO OR MAGNETQ ELECTREG MACHiNE.

SPECIFICATION forming part of Letters 1 atent No. 287,523, dated October 30, 1883.

Application filed September 13, 1882. (No model.)'

To all whom it may concern:

Be it known that I, THOMASA. Enrsoiwcf illenlo Par in. the county of Middlesex and State of New Jersey, have invented a new and useful Improvement in Dynamo or Magneto.

*lectric Machines, (Case Nof ifldfl and-*I'do nereby declare that the following is a full and exact description of the same, reference being had to the accompanying drawipg, and to the lettersof reference marked thereon.

The object I have in view is to produce a more efiicient construction of the field-of-force electro-magnet of dynamo or magneto electric machines, so that greater magnetic force can be produced than heretofore with the same mass of. iron and with the same consum )tion of electrical energy. This--1- aeeompn's by employing, in connection with the pblar extensions of a machine, two or more pairs of fiat or plate magnet-cores made of soft iron and wound separately with insulated wire,-

through which the electric current passes.

Each pair of flat soft-iron cores is preferably made in one piece, with a connecting back piece or yoke; but the back .piece or yoke may be a separate. piece secured to the fiat cores. The pairs of flat cores being separately wound, they may be connected in series in the field-circuit in multiple are or in multiple series. This construction of the field-of-force electro-magnet gives greater magnetic strength than the'round cores wound" separately, or

cores made up of a number of fiat plates covered with a common winding. 1 In connection with this construction of the cores, to give still greater eiiiciency, the concentrating convergent polar extensions'may be used.

The foregoing will be better understood from thedraw'ing, which shows in perspective a machine embodying the invention.

A is the revolving armature, having a contimzon'sl'b'obbin connected with the bars'of a ai'mmutator-cylinder, and being preferably it scifof cylindrical form, and l? N are the polar extensions of the field electro-magnet. These polar extensions have attached to them two or more pairs of flat soft-iron cores, B C, which are separately wound with insulated wire,'as shown at a, forming part of the field-circuit. The yoke 2), connecting each pair of fiat softiron cores, is preferably made in one piece with the cores. ,,The magnet-cores maybe ar ranged in a vertical or in a horizontal posi tion, and lie-attached to one side only of the polar extensions, or to opposite sides of the same.

To obtain greater efficiency, the polar extensions P N are constructed with bevel surfaces 0, as to contract the field-of-force vertic-ally or horiizontally, or in both directions. Machines constructed in this way have corresponding advantages when used as electric en gines or motors.

I do not claim herein the convergent. pole pieces, or the pole-pieces forming a cylindrical space in which the armature revolves, or the polar extensions, each made in one piece and provided with two or more cores,xthcse inventions being'clai'med in my application No.7? 1,756 and it is to be understood that all other patentable features of inventionshown' or described, but not claimed herein, are reserved for protection by other patents, and

have been or will be embodied in other appli fcations for patents.

' .What I claim is 1. In adynamo or magneto electric machine, the field-of-iorce elect-ro-magnet having two or more pairs of flat soft-iron cores provided with separate windings and two polarextensions, to which all of such cores are attached, substantially as set forth.

2. In a dynamo or n'iagneto electric machine, the field-ot-force electro-magnet composed of two polar extensions and two or more pairs of fiat soft-iron cores having separate windings and magnetioa-lly-separate yokes or back pieces, substantially as set forth.

8. In a dynamo or magneto electric machine, the field-otforccelectromagnet having two polar extensions and two or more pairs of flat soft-iron'cores provided with separate windings and yokes made integral with the cores, substantially as set forth.

4". In a dynamo or magnet-o electric ma chine, the combination, with the armature, of the convergent polar extensions, the flat softiron magnet-cores provided with separate windings and two polar extensions, to which said cores are attached, substantially as set forth.

This specification signed and witnessed this 3d day of June, 1882.

lVi'tnesses: THOS. A. EDISON.

ItICllD. N. Drnn, H. W. SEELY. 

